Heterojunction between Al2O3 and SnO2 thin films for application in transparent FET

Miguel Henrique Boratto, Luis Vicente de Andrade Scalvi, Jorge Luiz Barbosa Maciel Jr, Margarida Juri Saeki, Emerson Aparecido Floriano
2014 Materials Research  
Alternative materials for use in electronic devices have grown interest in the past recent years. In this paper, the heterojunction SnO 2 /Al 2 O 3 is tested concerning its use as a transparent insulating layer for use in FETs. The alumina layer is obtained by thermal annealing of metallic Al layer, deposited by resistive evaporation technique. Combination of undoped SnO 2 , deposited by sol-gel-dip-coating technique, and Al thermally annealed in O 2 -rich atmosphere, leads to fair insulation
more » ... o fair insulation when the number of aluminum oxide layers is 4, with 0.3% of the current lost through the gate terminal as leakage current. This insulation is not obtained for devices with alumina layer treated for long time, under room atmosphere, due to degradation of the insulating film and interfusion with the conduction channel even using Sb-doped SnO 2 . The annealing of Al deposited on soda-lime glass substrate leads also to the formation of a Si layer, crystallized at Substrate/Al 2 O 3 interface. The conclusion is that for an efficient insulation the thermal annealing must be short and then, O 2 -rich atmospheres are preferred.
doi:10.1590/1516-1439.285114 fatcat:x5rv22hwp5gzbaxlqfqqyvifb4